A wide variety of nasal drip appliances have been used in order to carry out a nasal drip of a predetermined medicinal solution into the nostril. Such a nasal drip appliance is disclosed in the Patent literature document 1 for instance. As shown in FIG. 14, a medicinal solution 106 is filled between a syringe barrel 102 and a plunger 104, and a nasal drop appliance 100 is inserted into the nostril. In this state, the plunger 104 is moved in a direction of an axis of the syringe barrel 102, whereby the medicinal solution 106 is sprayed from a plurality of spray holes 108 that have been formed on the leading end of the syringe barrel 102 to the nostril.
As shown in FIG. 15, the Patent document 2 discloses a nasal drip appliance 200 in which a medicinal solution 206 is filled between a syringe barrel 202 and a plunger 204, and a through hole for the medicinal solution 206 is formed in the leading end of the syringe barrel 202. In addition, a skirt valve 212 and an adapter 214 provided with a spray hole 208 of the medicinal solution 206 are attached to the leading end side of the syringe barrel 202. Moreover, a stopper 216 is fitted into the space between the rear end of the syringe barrel 202 and the rear end of the plunger 204.
For the nasal drip appliance 200, the medicinal solution 206 can be sprayed outward from the spray hole 208 of the adapter 214 only during a nasal drip of a medicinal solution. A movement distance of the plunger 204 can be limited by the stopper 216, whereby an amount of a spray of the medicinal solution 206 can be adjusted.
As shown in FIG. 16, the Patent document 3 discloses a nasal drip appliance 300 in which an adapter 314 provided with two spray nozzles 318 and 320 that can be inserted into two nostrils is attached to the leading end side of the syringe barrel 302 of the nasal drip appliance 300. By this configuration, a medicinal solution 306 can be sprayed into the both nostrils in one fell swoop.
On the other hand, as shown in FIG. 17 for instance, the Patent document 4 discloses a nasal drip appliance 400 of a so-called prefilled type in which a medicinal solution 406 has been stored and retained between a syringe barrel 402 and a plunger 404 before a usage. The prefilled type nasal drip appliance can be used as quick as possible when being used.
The prefilled type nasal drip appliance 400 can be used as quick as possible when being used. In addition, it is not necessary to carry out a filling operation of the medicinal solution 406 into a nasal drip appliance. Consequently, a mistake of a kind or an amount of the medicinal solution 406 can be prevented from occurring even in the event of an emergency, and a microbial contamination can also be prevented, thus improving a sanitarian level advantageously. As a result, the prefilled type nasal drip appliance 400 has been preferably used in recent years from an aspect of an efficiency of a medical treatment in a medical treatment site and an aspect of a prevention of a bacterial contamination.
The Patent document 5 discloses a nasal drip appliance 500 that has the following configuration. As shown in FIG. 18(a), only a gasket part 504a is removed from a plunger 504, and a medicinal solution 506 is stored and retained between a syringe barrel 502 and the gasket part 504a in advance. As shown in FIG. 18(b), a shaft part 504b of the plunger 504 is attached to the gasket part 504a during a usage, and an adapter 514 provided with a valve 512 is attached to the leading end side of the syringe barrel 502, whereby the nasal drip appliance 500 can be used.
A conventional nasal drip appliance and a conventional prefilled type nasal drip appliance that have the above described configurations enable a predetermined medicinal solution to be sprayed into the nostril.    Patent document 1: Japanese Patent Application Laid-Open Publication No. 2006-271940    Patent document 2: Japanese Patent Application Laid-Open Publication No. 2001-137344    Patent document 3: Japanese Patent Application Laid-Open Publication No. 11-114065    Patent document 4: Japanese Patent Application Laid-Open Publication No. 09-299484    Patent document 5: Japanese Registered Utility Model No. 3047521
However, for the nasal drip appliance 100 that is disclosed in the Patent document 1, immediately after a medicinal solution 106 is filled between a syringe barrel 102 and a plunger 104, the medicinal solution 106 leaks from the spray holes 108 that have been formed on the leading end of the syringe barrel 102 in some cases. Moreover, in the case in which the plunger 104 is moved slowly in a direction of an axis of the syringe barrel 102, the medicinal solution 106 slowly leaks from the spray holes 108, whereby the medicinal solution 106 cannot be in the form of a liquid mist. Consequently, the medicinal solution cannot be sprayed into the nostril in some cases.
The nasal drip appliance 200 that is disclosed in the Patent document 2 has a large number of components, and a production cost thereof is increased. Moreover, when the plunger 204 is moved in a direction of an axis of the syringe barrel 202, the valve does not function in the case in which a pressure of a certain level or more is not applied to the skirt valve 212. Furthermore, the medicinal solution 206 leaks from the spray hole 208, whereby the medicinal solution 206 cannot be in the form of a liquid mist. As a result, the medicinal solution 206 in the form of a liquid mist cannot be sprayed into the nostril in some cases.
The nasal drip appliance 300 that is disclosed in the Patent document 3 is an appliance that sprays the medicinal solution 306 into the both nostrils at one time. Consequently, the nasal drip appliance 300 cannot be used in the case in which a medicinal solution is sprayed into only a nostril on one side, and a use application is restricted. Moreover, the nasal drip appliance 300 is large in size, whereby portability thereof is deteriorated and a production cost thereof is increased.
The nasal drip appliances 400 and 500 that are disclosed in the Patent documents 4 and 5, respectively, have a large number of components, and a production cost thereof is increased. Moreover, when the plunger 404 or 504 is moved in a direction of an axis of the syringe barrel 402 or 502, the medicinal solution 406 or 506 cannot be in the form of a liquid mist in the case in which a pressure of a certain level or more is not applied to the plunger 404 or 504. As a result, the medicinal solution 406 or 506 in the form of a liquid mist cannot be sprayed into the nostril in some cases.
Moreover, the nasal drip appliance that is disclosed in the Patent document 2 or 3 can also be applied to a prefilled type nasal drip appliance. However, even in this case, the problems that have been described above cannot be solved.
As described above, a conventional nasal drip appliance and a conventional prefilled type nasal drip appliance have the problems that have been described above. In the case in which a medicinal solution is to be sprayed, it is determined whether or not a medicinal solution is sprayed with a certainty depending on the level of a power force of a person that handles a nasal drip appliance. Consequently, in the case in which a nasal drip appliance is handled, all people cannot always spray a medicinal solution into the nostril with a certainty in the same way.
The present invention was made in consideration of such conditions, and an attention is focused on a prefilled type nasal drip appliance among the nasal drip appliances. An object of the present invention is to provide a prefilled type nasal drip appliance that enables a production cost thereof to be suppressed, that can be handled by all people in the same way, that can be easily handled, and that enables a medicinal solution to be sprayed into the nostril with a certainty.